1.
num = 3
def fun() :
    num = 5
    print('函数内局部变量num的值：', num)
fun()
print('函数外全局变量num的值：', num)
2.
num = 5
def fun():
    global num
    num += 1
    print('函数内num的值：',num)
fun()
print('函数外num的值：',num)
3.
def outer():
    num = 1
    def inner():
        nonlocal num
        num = 2
        print('inner函数中num的值', num)
    inner()
    print('outer函数中num的值：', num)
outer()
4.
stu = [{'num':'201801', 'name':'王五', 'score':89},
    {'num':'201802', 'name':'刘军', 'score':95},
    {'num':'201803', 'name':'李梦', 'score':85}]
stu.sort(key=lambda x: x['score'])
for s in  stu:
    print('学号:',s['num'],'姓名:',s['name'],'成绩:',s['score'])